How to Find Your Sports Bra Size
If you get chafing, your sports bra feels too tight, or you don't feel supported enough during your runs, it could be down to size. A lot of products come in alpha sizing (Small, Medium, Large, etc.), which just isn't how our breasts work - knowing your band and cup size, or even better your measurements, makes a real difference. Most of us don't: over 70% of women are reportedly wearing the wrong size bra.
Many of us are still wearing whatever we were fitted for as teenagers, if we were ever properly fitted at all. Getting it right isn't as hard as the industry makes it out to be, so here's what you need to know.
If you have a measuring tape
The band and cup sizing works like this:
- Measure your underband in inches → this is your underband measurements (or if you measure in cm, this is your European underband)
- Measure the widest part of your chest (overbust)
- The difference between your overbust and underband measurement is your cup volume
difference of 1 inch → A; 2 inches → B; 3 inches → C; 4 inches → D
Some brands vary from this formula, but if you have the underband and overbust measurement, you can usually figure out your best size from their size chart.
Beyond the tape measure
The above is a great starting point, but our chests aren’t 2D things. During testing, we fitted over 15 women and found that often things like the shape, spacing or volume of your breasts can also impact your sizing.
This is why fitting experts tend to look beyond the tape at how the bra fits on your body.
- Underband fit → not too snug, not too loose. You should be able to pull the underband a couple inches and it shouldn’t feel like you’re struggling to take a full breath. Most people wear an underband that’s too big, which is why people end up with chafing around that area.
- Cup fit → you don’t want any bulging over the cups or out of the bra. The whole of the breast tissue should be enclosed. If it isn’t, go up a cup volume. Go down a size if the cup is gaping and there is space between your boobs and the bra.
- Straps → this is less about size, but check they’re comfortable. Ideally, the bra has adjustable straps.
What even is sister sizing?
Sister sizing groups sizes by cup volume.
I personally think sister sizing is why so many women wear the wrong size bra. The idea is that going from a 32D to a 34C or 30DD is basically keeping the size the same. It isn’t - because women’s bodies don’t scale linearly.
For sports bras especially, the underband is where most of the support comes from. So I wouldn’t go up or down sister sizes, unless the band is too loose or too tight.
And that’s it! I implore you to go to a bra shop and try on a few sizes and check it against above checklist.
Stana has partnered with BraRista to help you with finding your size at home via the chatbot. If you’re still unsure, feel free to reach out and our team will be happy to help.